1. Field of the Invention
The present invention relates to a photographic camera provided with a pseudo focal length photographing mode.
2. Description of the Prior Art
There has been disclosed such a camera employing the pseudo focal length photographing mode in U.S. Pat. No. 4,583,831 and Japanese patent laid open No. 26721/1979 in which a pseudo photographing information is recordable on a negative film. The term of pseudo photographing used herein means that a portion of the picture on a negative is selected and printed on a print with a predetermined magnification value, so that the print has a telephoto or a close-up format.
In a pseudo focal length photographing mode camera in which the light measurement range is selectable between an average light measurement and a spot light measurement, in case the average light measurement is selected and a picture is taken under the pseudo focal length photographing mode (referred to as pseudo mode or PFL mode) when an excessive bright object or a dark object is situated in the scope of the field of view to be recorded on the negative film but is out of the printed range to be printed on the paper, the light measurement value under such condition mentioned above is an unsuitable value for the printed range.
Moreover, there has been known to provide a camera shake warning device in which warning is made when the shutter speed is slower than a predetermined critical speed at which speed there may occur a bad effect of the camera shake on the print. In such cameras, the critical shutter speed used as the reference speed for warning the camera shake is set corresponding to the focal length of the photographic lens. Accordingly, in a camera for which an interchangeable lens is available, there are provided various functions to automatically read the focal length of the interchangeable lens, to decide the shutter speed used as the reference speed of the camera shake warning, to select a desired program for deciding the relation between the shutter speed and aperture value and to control the light emitting angle of a flash light.
On the other hand, in the pseudo focal length photographing mode camera, even if the actual focal length of the lens mounted to the camera is constant, the pseudo focal length may change according to the magnification value of the print, therefore, the critical shutter speed for preventing the effect of the camera shake must be changed depending on the equivalent focal length since the pseudo focal length is changed corresponding to the magnification value at the time of enlarging the size of the photographing object to be printed. However, the conventional camera of this type is not provided with the function of automatically selecting the suitable critical shutter speed for the camera shake warning.